Abstract Objective This study attempts to clarify the causes behind a partially changed oxygen pressure by observing subcutaneous microcirculatory perfusion (abbr. SMP) and transcutaneous oxygen pressure (TcPO2) along the skin of Large Intestine Channel (LI) simultaneously. Methods Take SMP and TcPO2 as the two main indexes and one-cun-above-LI6 (Pianli), LI10 (Shousanli), and LI13 (Shouwuli) as the three destined points along the skin of LI to test the indexes on the destined points in 15 healthy volunteers using PeriFlux System 5000 and to observe their variation during acupuncturing Hegu (LI4). Besides, the experiment has also been performed in another 8 volunteers with all the other conditions equal but heating Hegu as the intervention instead. To investigate the difference in energy metabolism between Meridian and Non-Meridian further, SMP was observed on acupoints LI10, LI13, and their bilateral Non-Meridian control points. Results In Hegu acupuncturing group, the means of the two main indexes in the three vertical levels mentioned above before acupuncture and during acupuncture were analyzed by homebody paired sample T test, and SMP during acupuncture was a little higher than that before acupuncture, whereas TcPO2 significantly decreased (P < 0.01). In Hegu heating group, the result was similar. In Non-Meridian control group, the microcirculatory perfusion was slightly higher, relative to the controls group. Conclusion A reduced TcPO2 along the meridian course when acupoint being stimulated is not caused by reduced oxygen supply but rather by increased oxygen consumption resulted from enhanced energy metabolism in some relative tissues.